QDNAAdvisory and architecture for LLM inference and training platforms, on-premises or hybrid

Running Nemotron 3 Ultra on H200 SXM server

Nemotron 3 Ultra has 550 billion parameters. H200 SXM server offers 1,128 GB of HBM3e across 8 GPUs memory. This page puts the two side by side.

Short answer. Nemotron 3 Ultra fits comfortably on H200 SXM server. In FP8, its weights take about 632 GB of the 1,128 GB available, leaving 496 GB for the attention cache and concurrency.

How much memory does Nemotron 3 Ultra need?

Weights take the parameter count multiplied by the format size, plus a 15% runtime margin for activations and buffers. In FP8 the calculation reads: 550 billion parameters × 1 byte (FP8) = 550.0 GB of weights; × 1.15 runtime margin = 632.5 GB. The attention cache sits on top: it grows with context length and with the number of concurrent requests, so it is sized case by case.

FormatWeights in memory On this machineWhat the format costs
FP161,265 GBdoes not fitfull precision, the quality reference
FP8632 GBfitsnegligible loss on most tasks
NVFP4316 GBfitsBlackwell format, native FP4 compute
Q4379 GBfitsblock quantisation, broadly supported

Model sheet: 550 billion parameters, 55 billion active per token, 262,144-token context, OpenMDW 1.1 licence. 550 billion announced; the BF16 repository holds 560 billion elements (1,121 GB). The card claims “up to 1M” context, config.json declares 262,144.

Nemotron 3 Ultra activates 55 billion parameters per token out of 550 billion. Active parameters govern speed, not footprint: every expert stays resident in memory. Confusing the two under-sizes the machine by an order of magnitude.

What is left to serve requests?

Nemotron 3 Ultra fits comfortably on H200 SXM server. In FP8, its weights take about 632 GB of the 1,128 GB available, leaving 496 GB for the attention cache and concurrency. The remaining margin decides how many concurrent requests and how much context the machine sustains. By QDNA convention a machine “fits” when the weights take at most 75% of its memory; beyond that it “barely fits” and forces a limit on context or on concurrency. The attention cache is not calculated on this page. These models’ architectures (compressed latent, linear or sparse attention, Mamba layers) share no per-token formula; it is measured on the machine, with the target context and concurrency [TO BE MEASURED].

H200 SXM server: indicative price about €453k excl. VAT, not contractual. Source: 8-GPU H200 141 GB server with two Xeon Gold 6538Y+ listed at £387,785 by CTO Servers on 2 September 2026, converted at the ECB rate of £0.857 per €1. The machine targets the GE segment.

Where else can Nemotron 3 Ultra run?

See the Nemotron 3 Ultra and H200 SXM server fact sheets.

How much memory does Nemotron 3 Ultra need?

In FP8, weights take about 632 GB including the runtime margin. The attention cache sits on top and depends on context.

Does Nemotron 3 Ultra fit on H200 SXM server?

Nemotron 3 Ultra fits comfortably on H200 SXM server. In FP8, its weights take about 632 GB of the 1,128 GB available, leaving 496 GB for the attention cache and concurrency.

Method and sources

Memory footprints are calculated, not measured: a reading on real hardware may differ depending on the engine and the exact weight format. Every figure below carries its source and the date of its last check.